Various types of computing and media devices, such as desktop computers, portable computing devices, televisions, and other display devices, are increasingly designed with a touch-screen display for user input and touch interaction. The various types of devices, as well as an all-in-one computer (PC) with a movable display, can be designed for multi-position display, and used in an upright position as a vertical display, flat on a table as a horizontal display, or in an angled position between vertical and horizontal. For a device such as an all-in-one PC with a movable display, a number of display positions are undesirable for either usability, or balance and stability reasons. Further, for a multi-pivot link, the display positions depend on the rotation of multiple dependent axes, and locking out undesirable display positions requires coordination between the multiple dependent axes with complicated and costly mechanical linkages.
When a set of masses that are connected by two axes are moved, mechanical counter-balancing quickly becomes difficult or impossible unless one or both of the axes are positioned at the center of each connected mass, which makes the respective counter-balance force zero. The counter-balance force needed at each axis is dependent on the angle relative to the surface base for both masses. Further, because the two angles for the axes are unrelated, the spring resistance needs to be non-linearized, such as by a CAM or other device, and the forces need be correlated through some linkage between the two axes. Designing such a precise counter-balanced mechanical system is prohibitive in a small form factor and, if not designed well, can result in a poor user experience and feel when the display device is moved or tilted. Without precise counter-balancing, the apparent weight of the masses will change across the range of motion of the device. In most cases, a friction component is added to compensate for any mismatch in counter-balancing so that the device doesn't drift or fall over, which, once again, results in a poor user feel when the display device is adjusted to a display position.